How to Drill & Tap Aluminum

by C.L. Rease

The qualities that make aluminum lightweight create problems when you are creating a threaded hole in the material. Drill bit and taps used on aluminum will clog as they remove material from the area. Each tool will fail to cut the aluminum once clogged. Keeping the tools free of aluminum ensures a threaded hole able to hold a fastener.

Step 1

Reference a tap chart to determine the drill bit size required for the threaded hole.

Step 2

Secure the drill bit in a drill motor. Cover the end of the drill bit and the surface of the aluminum with cutting fluid.

Step 3

Place the point of the coated drill bit on the aluminum. Pump the trigger of the drill motor to drill into the metal. Apply additional cutting fluid to the aluminum as you drill.

Step 4

Secure a tap in the handle of a tee-handle tap wrench. Apply cutting fluid to the threads of the tap. Pour cutting fluid into the drilled hole.

Step 5

Turn the tap handle clockwise to thread the tap into the hole. Reverse the direction of the tap when you have difficulty turning the tap into the aluminum.

Step 6

Remove the tap from the threaded aluminum hole. Run a wire brush around the threads of the tap.